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Black carbon (BC) is a pollutant aerosol affecting climate and human health. Light absorption coefficients of black carbon (Babs) were measured using an aethalometer model AE33 at wavelengths 370, 470,520,660,880, and 950 nm. Babs for the seven wavelengths at seven sites in Jordan fluctuated with time and peaked at rush hours. The daily average values for all sites were inversely proportional to the wavelength. The average daily visibility values in the seven Jordan sites varied between 72 km and 211km. In the Irbid site, the daily average visibility values for 7-13 Nov. 2021 varied between 43 km and 107 km. BC varied from hour to hour and from day to day. The daily average values of BC in Irbid for the period of 7 -13 Nov. 2021 varied between 2.24 μg.m-3 and 4.66 μg.m-3. BC peaked at the rush hour and had the lowest values on Friday. About 90% of the measured BC was from fossil fuel sources and 10% from biomass-burning sources.

INTRODUCTION : Despite the broad improvement in air quality, air pollution remains a major leading global risk factor for ill health and deaths each year. Air pollution has a significant impact on both health and economic growth in Africa. This paper reviews the health impacts of air pollution and the benefits of air pollution mitigation and prevention on climate change. METHODS : We conducted a narrative review and synthesized current literature on the health impact of air pollution in the context of changing climate in Africa. RESULTS : Particulate matter (PM2.5) concentrations in Africa pose significant health risks due to various sources, including household fuels and industrial emissions. Limited air quality monitoring hampers accurate assessment and public health planning. Africa’s rapid urbanization exacerbates air pollution, impacting vulnerable populations disproportionately. Renewable energy adoption and improved monitoring infrastructure are crucial for mitigating air pollution’s economic and health impacts. Recommendations include adopting air quality standards, identifying pollution sources, and prioritizing interventions for vulnerable groups. Integrating renewable energy into development plans is essential for sustainable growth. African leaders must prioritize environmental policies to safeguard public health amid ongoing industrialization. CONCLUSIONS : Air pollution prevention remains a vital concern that requires leaders to engage stakeholders, and other opinion leaders in society. African leaders should proactively explore new avenues to integrate non-polluting renewable energy sources such as solar power, wind and hydropower into their national development plans.

This study presents the emission profiles of n-alkanes for different vehicular sources in two Brazilian cities. Atmospheric particulate matter was collected in São Paulo (Southeast) and in Salvador (Northeast) to determine n-alkanes. The sites were impacted by bus emissions and heavy and light-duty vehicles. The objective of the present study is to attempt to differentiate the profile of n-alkane emissions for particulate matter (PM) collected at different sites. PM concentrations ranged between 73 and 488 µg m−3, and the highest concentration corresponded to a tunnel for light and heavy duty vehicles. At sites where diesel-fueled vehicles are dominant, the n-alkanes show a unimodal distribution, which is different from the bimodal profile observed in the literature. Carbon preference index values corresponded to anthropogenic sources for most of the sites, as expected, but Cmax varied comparing to literature and a source signature was difficult to observe. The main sources to air pollution were indicated by principal component analysis (PCA). For PCA, a receptor model often used as an exploratory tool to identify the major sources of air pollutant emissions, the principal factors were attributed to mixed sources and to bus emissions. Chromatograms of four specific samples showed distinct profiles of unresolved complex mixtures (UCM), indicating different contributions of contamination from petroleum or fossil fuel residues, which are unable to resolve by gas chromatography. The UCM area seemed higher in samples collected at sites with the abundance of heavy vehicles.

Is there precedence in Earth history for the rapid release of carbon dioxide (CO₂) by fossil fuel burning and its environmental consequences? Proxy evidence indicates that atmospheric CO₂ concentrations were higher during long warm intervals in the geologic past, and that these conditions did not prevent the precipitation and accumulation of calcium carbonate (CaCO₃) as limestone; accumulation of alkalinity brought to the ocean by rivers kept surface waters supersaturated. But these were steady states, not perturbations. More rapid additions of carbon dioxide during extreme events in Earth history, including the end-Permian mass extinction (251 million years ago) and the Paleocene-Eocene Thermal Maximum (PETM, 56 million years ago) may have driven surface waters to undersaturation, although the evidence supporting this assertion is weak. Nevertheless, observations and modeling clearly show that during the PETM the deep ocean, at least, became highly corrosive to CaCO₃. These same models applied to modern fossil fuel release project a substantial decline in surface water saturation state in the next century. So, there may be no precedent in Earth history for the type of disruption we might expect from the phenomenally rapid rate of carbon addition associated with fossil fuel burning.

This study presents the characteristics of black carbon aerosol (BC) over a high-altitude site, Mahabaleshwar during the monsoon season. The mass concentration of BC exhibits a morning peak and a daytime build-up with a mean mass concentration of 303 ± 142 ng m −3 . The simultaneous measurements of aerosol particle number concentration (PNC), cloud condensation nuclei concentration (CCN), and non-refractory particulate matter less than 1 μm size (NR-PM 1 ) were also made by using a Wide-Range Aerosol Spectrometer (WRAS), CCN counter and Aerosol Chemical Speciation Monitor (ACSM) respectively. The source apportionment using wavelength-dependent light absorption model reveals the dominance by wood burning sources during morning hours and traffic sources during remaining hours of the day. The diurnal variation of PNC follows the variability of BC mass concentration. However, CCN concentrations were high during the morning hours coinciding with the increased fractional contribution of organics. The k -means clustering coupled with fuzzy algorithm highlights the effect of different sources on aerosol size distribution. On the basis of size distribution curve, the 3 clusters were attributed to wood burning (mean diameter range: 50–100 nm), traffic (30–50 nm), and background aerosols (65–95 nm). The combined analysis of k -means clustering, fractional contribution of organics, and kappa variation suggests that higher CCN concentration during morning is mainly attributed to probable emission of the water-soluble organic/inorganic compounds from wood burning.

What are we doing to our climate? Emissions from fossil fuel burning have raised carbon dioxide concentrations 35 percent higher than in the past millions of years. This increase is warming our planet via the greenhouse effect. What is climate change doing to and for us? Dry regions are drier and wet ones wetter. Wildfires have increased threefold, hurricanes more violent, floods setting record heights, glaciers melting, and seas rising. Parts of Earth are increasingly uninhabitable. Climate change requires us to act as a global community. Climate justice enjoins emitters to pay the social‐environmental costs of fossil fuel burning. This would expedite green solar, wind, and next‐generation nuclear energy sources. Individuals should conserve resources, waste less food, and eat a plant‐rich diet.

While energy efficiency projects could partly meet new energy demand more cheaply than new supplies, weak economic institutions in developing and transitional economies impede developing and financing energy efficiency retrofits. This book analyzes these difficulties, suggests a 3-part model for projectizing and financing energy efficiency retrofits, and presents thirteen case studies to illustrate the issues and principles involved.

Based on an estimated global fuel consumption of 2.57 × 10^sup 15^g(C) y^sup -1^ and the assumption thatthe fossil fuel burned in Austria is globallyrepresentative, an upper limit of 0.021 (+150%, -50%)Tg y^sup -1^ for global CH^sub 3^CN emission dueto fossil fuel burning was obtained from the relativeenhancement of the concentrations of toluene, benzene,and acetonitrile (methyl cyanide) during strong,short-term traffic pollution. This is less than 6% ofthe total global budget of CH^sub 3^CN, which is dominatedby an emission rate of 0.8 Tg y^sup -1^ from biomassburning.[PUBLICATION ABSTRACT]

Climate change is already a reality. This is evidenced by the acceleration of global temperature increases, the melting of ice and snow covers, and rising sea levels. Latin America and the Caribbean region (LCR) are not exempt from these trends, as illustrated by the changes in precipitation patterns that are already being reported in the region, as well as by observations of rising temperatures, the rapid melting of Andean tropical glaciers, and an increasing number of extreme weather events. The most important force behind climate change is the rising concentration of greenhouse gases (GHGs) in the earth's atmosphere driven mainly by manmade emissions of carbon dioxide (CO2) and other greenhouse gases. Because of inertia in the climate system, the planet is likely to continue warming over the twenty-first century, and unless emissions are significantly reduced, this process could accelerate, with potentially very serious consequences for nature and mankind. There is still, however, a high degree of uncertainty regarding the specific drivers, timing, and impact of global climate change, as well as about the costs and efficacy of actions aimed at either mitigating it or dealing with its physical and economic impacts. As a result, it is very hard, at this point, to unambiguously determine economically efficient emission pathways for which the benefits of actions to mitigate climate change will exceed the costs of those actions. Despite these problems and uncertainties, there is increasing evidence suggesting that urgent action is needed in order to alter current emission trends so as to avoid reaching GHG concentration levels that could trigger large and irreversible damages. Negotiations are under way and are scheduled to be concluded in 2012 with a new agreement on a way forward. At the same time, individual countries are also considering how to respond in their own domestic policy to the challenges of climate change. LCR governments and civil society should be well informed about the potential costs and benefits of climate change and their options for decisions that will need to be made over the next decades as well as the global context in which these decisions must be taken. At the same time, the global community needs to be better informed about the unique perspective of the LCR, problems the region will face, potential contributions the region can make to combat global warming, and how to unlock the region's full potential so as to enable it to maximize its contribution while continuing to grow and reduce poverty. This report seeks to help fill both these needs.